Hydraulic dredger



(No ModeL) H. L. PIKE & A. W. FERGUSON.

HYDRAULIC DREDGER.

No. 263,429. Patented Aug. 29,1882.

'NITED STATES PATENT OFFICE.

HERVEY L. PIKE AND ALBERT W. FERGUSON, OF ASTORIA, OREGON.

HYDRAULIC DREDGER.

SPECIFICATION formingpart of Letters Patent No. 263,429, dated August29, 1882.

Application filed May 22, 1882. (No model.)

the followingto be a full, clear, and exact description thereof.

Our invention relates to an apparatus for dredging bars and shallowplaces in harbors, rivers, and other places; and it consists of apneumatic and hydraulic tank having nozzles which are so placed thatthey will discharge a current or currents of water forcibly downwardfrom the bottom when pressure is applied. The upper part of the tank isprovided with an air-chamber, and a flexible pipe has one endopeninginto the tank, while the other is led forward to a vessel bywhich the tank is towed from place to place. Upon this vessel are twosets of pumps, one for air and the other for water. Each of these pumpsis connected with the flexible hose, and a suitable valve or cookenables the operator to use either at will. When the tank is to be movedair is forced in to float it. When it arrives at the place to be dredgedwater is admitted, (the air escaping,) and it settles upon the bottom orbar, being ballasted for the purpose. The airconnections being then shutoff and that with the Water-pump opened, the pressure forces the waterout through the nozzles in the bottom and loosens the mud, so that itwill be carried away by the current.

Referring to the accompanying drawings for a more'complete explanationof ourinvention, Figure l is a perspective view. Fig. 2 is alongitudinal vertical section. Fig. 3 shows connection with pump.

A is a tank, which may be made of any suitable dimensions, size, andmaterial. Wehave shown it in the present case made of boiler or otheriron plates riveted together so as to be water-tight, and having anair-chamber, B, upon the top, at or near the center. This tank isdivided into two compartments, 0 and D, the upper one connecting withthe air-chamber B and with the inlet and discharge openin gs. The lowercompartment, D, contains the ballast, which is preferably of metal,although water-ballast may be employed in some cases, if desired.

Nozzles E extend from the compartment 0 through the compartmentD,andopen through the bottom, so as to discharge downward. These nozzles aremade of such shape as to deliver-their stream with the best effect whenthe pressure is applied.

From the top of the tank a pipe, F, leads. This pipe is'flexible andextends forward to a vessel which conveys the apparatus to the pointwhere it is to be used.

. A suitable connection, G, is made upon the tank, from whichtowing-hawser leads forward to the vessel.

Two pumps, H I, are fixed upon the vessel, the pump H being an air-pumpand I a waterpump. Both of these pumps connect with the main flexiblepipe F, and suitable valves or cocks are provided at points wherecommunication with either one or the other may be out off.

The operation will thus be as follows When the apparatus is to be usedthe air-pump is set in motion and. air forced into the tank untilitfloats, the water escaping through the nozzles E in the bottom. The tankis then towed to the point where it is to be used, and a valve near thepump H, or in some part of the pipe F, is opened to allow the air toescape from the tank. The water rushes in through the nozzles E andfills the tank, which settles upon the surface to be operated upon. Thepassage to the air-pump being closed, that to the water-pump is opened,and that pump is set in motion, forcing a stream of water into the tankand acting to drive the water forcibly through the nozzlesE against thesand or mud composing the bottom. The ballast and the weight of the tankwill be sufficient to keep it upon the bottom, and a steady current ofwater will thus be forced through the nozzles,

tearing up the sand and mud, so that the current will carry it off.

In some cases it will be found desirable to move the apparatus slowlyover the bottom while the pump is at work, so as to work continuouslyand in others the work may be done at short intervals, and the currentwill do the rest.

The apparatus is simple, effective, and cheap.

It will be manifest that any number of either air or water pumps may beemployed with suitable connections, so that the rate of work may beregulated.

Having thus described our invention, what we claim as new, and desire tosecure by Letters Patent, is

1. A dredging or scouring apparatus consisting of the tank A, having thedischargenozzles E, opening downward throughits bottom, and asupply-pipe, F, through which wa ter may be discharged into the tankunder pressure, substantially as and for the purpose herein described.

2. In a dredging 0r scouring apparatus, the tankA,having Water andballast compartments 0 and D, an air chamber, and the nozzlesE,discharging through the bottom, in combination with the flexible pipeF for air or water, and the air and water supply pumps H and I, withtheir cocks or valves, substantially as herein described.

3. The means herein described for dredging or scouring harbor-bars orother obstructions, consisting of a compartment-tank having numerousdischarge-nozzles in the bottom and a supply-pipe at the top, throughwhich water may be introduced under pressure, substantially as shown.

4. Ina dredging or scouring apparatus consisting of a tank havingdischarge-nozzles through its bottom, the means for floating andadjusting the draft of said apparatus, consisting of the air-chamber andthe connectingpipe and air-pump, substantially as herein described.

In witness whereof we hereto set our hands.

HERVEY L. PIKE. ALBERT \V. FERGUSON. Vitnesses A. GnosBY, II. 0. HIPPLE.

